TLR4 and COVID-19: Previous studies have provided the evidence of inflammatory factors in the blood of COVID-19 patients, indicating the presence of a cytokine storm in the lung.22,23 We detected most of the molecules associated with the nuclear factor-κB (NF-κB) pathways, including the upstream proteins such as receptors (TLR4, CD40, and BAFF) and TRAF protein family members (TRAF2, TRAF3, and TRAF6), and downstream cytokines (interleukin-6 (IL-6), IL-8, TNFα, and IFNα, and ICAM1) or chemokines (CXCL12), finding them all upregulated in the COVID-19 lungs (Fig. 3).